/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.sdk.state;



import com.bff.gaia.unified.sdk.annotations.Experimental;

import com.bff.gaia.unified.sdk.annotations.Experimental.Kind;



import javax.annotation.Nonnull;



/**

 * A {@link ReadableState} cell containing a bag of values. Items can be added to the bag and the

 * contents read out.

 *

 * <p>Implementations of this form of state are expected to implement {@link #add} efficiently, not

 * via a sequence of read-modify-write.

 *

 * @param <T> The type of elements in the bag.

 */

@Experimental(Kind.STATE)

public interface BagState<T> extends GroupingState<T, Iterable<T>> {



  @Override

  @Nonnull

  Iterable<T> read();



  @Override

  BagState<T> readLater();

}